8.5 Computer Security

Computer security is a branch of computer technology known as information security as applied to computers and networks. The objective of computer security includes protection of information and property from theft, or corruption, while allowing the information and property to remain accessible and productive to its intended users.

Antivirus
An antivirus is a program that protects the computer from virus infections. The antivirus program may repair an infected file, or deleting it. The antivirus program should update itself frequently. The antivirus programs should run in the background all the time. Before installing a new antivirus, we should uninstall any other antivirus programs. Using two or more antivirus programs at the same time can cause problems.

Firewalls
Firewall is a program or device that blocks unrequested communications from the Internet, preventing the computer from responding to attempts to access. There are two types of firewalls:

Software firewall: it is built-in to the computer's operating system.

Hardware firewall: it is a piece of equipment that is designed to operate as a firewall.

8.5 Computer Security

Passwords
Passwords are often used to protect objects in the computer system. For instance, a password could be associated with each resource (such as a file). Different passwords may be associated with different access rights. For example, different passwords may be used for each of the following file operations: reading, appending, and updating. Passwords can be guessed by knowing the user or by trying all possible combinations of letters, numbers and punctuation, until the password is found. Passwords can be either generated by the system or selected by a user. A system could use a set of paired passwords, the system randomly selects and presents one part of a password pair; and the user must supply the other part.